Grinding device



'Sept-1, 1935- G. MAKARol-F 2,052,837

GRINDING DEVICE Filed Aug. 16, 1954 3 Sheets-Sheet l Inventm v -rjory Q/QI/rff www@ Attorney Sept, 1, 1936.u G, MAKAROFF l2,052,837

GRINDING DEVICE Filed Aug. 1e, 1954 s-sheets-sheet 2 :m16 Il i s g l 'l I J I i l I L Attorney Sept. l, 1936. G MAKAROFF 2,052,837 GRINDING DEVIICE Filed Aug. 16, 1934 3 Sheets-Sheet 3 J \\\\\\\\\\K\\\\\\\\\ \\l Z3 y ff' Patented Sept. 1, 1936 stares PA'lENT OFFICE 2 Claims.

This invention relates to devices for grinding tools, and more particularly for grinding blades of various types.

The invention comprehends the use of a conventional power driven saw organization wherein a grinding disk Vis substituted for the saw; and also the provision of improved blade holding or clamping means whereby the angularity ofthe blade may be adjusted at will to insure proper contact of the beveled edge of the blade with the periphery of the grinding disk in a manner to afford an almost perfect sharpening of the blade.

The invention, together with its objects and advantages, will be best understood from the following description taken in connection with the accompanying drawings wherein:

Figure l is a side elevational view illustrating the application of the invention.

Figure 2 is a top plan view thereof.

Figure 3 is a top plan view of one form of blade clamping' and holding device.

Figure 4 is a bottom plan View thereof.

AFigures 5 and 6 are detail views taken substantially on the lines 5--5 and 6--6 respectively of Figure 3.

Figure 'l is a detail view taken substantially on the line 'L -'l of Figure 5.

Figure 8 is a perspective View of a jaw member.

Figure 9 is a sectional view through the jaw member.

Figure 10 is a top plan View of a second form of blade clampand holder.

Figure 11 is a bottom plan view thereof.

Figure l2 is a detail sectional view taken substantially on the line I2--l2 of Figure 10.

Referring to the drawings by reference numerals, it will be seen that a conventional power driven saw assembly is utilized the same in the present instance consisting of a suitable support l to which is pivoted in the usual manner as at 2 the work table 3 that is slotted in the usual manner to receive the Saw. However, in the present instance, the saw is removed and a grinding disk l is substituted therefor and operates through the slot in the table 3 as clearly shown in Figures l and 2. The shaft on which the grinding disk il, in the present instance, is supported is driven from a suitable electric motor 5 through the medium of belt and pulley means 6 and in the usual manner. The usual means I is provided for securing the work table 3 at the desired angular adjustment relative to the horizontal.

The top of the table 3 is provided with the usual guide grooves 8 in a selected one of which is equipped with suitable means hereinafter more 10 fully referred to whereby the body of the device may be supported at the desired angle relative to the top 3 to insure the desired contact of the beveled edge of the blade being sharpened with the periphery of the grinding disk 4.

In the form shown in Figures 3 to 'l inclusive, the body of the blade clamp and holder consists of a rectangular block of wood or other suitable material and indicated by the reference numeral II. A pair of strips I2 of metal or other suitable material has the major portions thereof fitting in grooves provided therefor in the underface of the body II and extending transversely of the body. The strips I2 are secured to the body through the medium of any number of suitable fastening devices such as screws I3. At their forward or free ends the strips I2 are rabbeted to form jaws I4.

Cooperating with the jaws I4 are removable jaws I5 which consist of rectangular pieces of wood or the like having a down-turned end I5' overlying the jaws I4 and cooperable therewith for clamping a portion of the blade to be sharpened therebetween. In the present instance, I have shown the jaws I5 removably secured to the strips I2 through the medium of nger screws I6 that thread into suitably alined openings I8 and i9 respectively provided in the strips I2 and jaws I5. To prevent the jaws I5 from rotating relative to the jaws Ill strips I2 on their upper sides are provided with pins that are engaged by notches 2l provided in the rear end edges of the jaws I5.

In the end face thereof the body I I between the strips I2 is formed with a transverse groove or pocket in which is hinged as at one end, and as at 22 an adjustment plate 23 that normally ts within the pocket, the latter being indicated by the reference numeral 24.

An adjustment screw extends through the body II adjacent the forward end of the pocket 24 and is provided with a threaded collar 26 that rests on the top face of the body II, the screw 25 threading through a nut 2l seated in a recess provided in the underside of the body II, which nut is retained within its recess through the medium of a plate 28 secured in position through the medium of screws 29. Obviously, by threading the screw 25 downwardly into engagement with the plate 23 the latter will be forced to swing, for example, to the dotted line position shown in Figure for varying the angular position of the body I I when it is desired to adjust the angular position of the blade during the sharpening thereof without disturbing the set position of the table 3. In this connection, it will be thought apparent that if desired the 4angular relation of the blade in the holder in obtaining the proper contact of the beveled edge of the blade with the grinding disk 4 may be effected by varying the angle of the table or bench top 3. It will be apparent that either by the adjustment of the screw 25 or the adjustment of the tableY 3 the adjustment of the blade may be effected, very minute adjustments being effected through the medium of the screw 25.

When it is not intended to use the screw 25 andrplate23 yfor attaining this adjustment the plate 23 may be secured within the pocket 24 against casual displacement through the medium of a suitable screw 30.

The body I I at. the edge thereof opposite to the jaws I4 and I5 .is provided with a metallic reinforcing plate 3I. Y Y Y In using-the device, it will be apparent that the blade 32 Yto beY sharpened has the end portions thereof clamped between the jaws I 4 and I5. The square or miter gauge 9 is set at the desired position when the reinforced edge 3I of the body I I is then placed against the member Il] as shown in Figures 1 and 2 with the beveled edge of the blade32 in contact with the periphery of the diskll. As the driven disk l revolves, the body I I with the associated parts may be moved back and forth transversely across the'table 3 with the edge vof the blade 32 ,at all times in contact with the periphery of the grinding disk 4 to insure a smooth even edge for the blade.

f For the holder just described there may be substituted a holder and clampy of the type shown in Figures 10 to l2 inclusive. In this form the holder consists -of comparatively few parts and will be more light in weight than the holder hereinv first described. The second form of holder comprises a body I I laterally extended at its rear end asat Ila and at said end being adapted to have the edge thereof engaged with the fence or guide-barv Ill in thesame manner as the edge SI of the first type `of clamp engages said fence or `guide member. Also, at the edge thereof opposite to the first named edge, the portions of the body II are extended to provide fixed jaws I4' similar to the fixed jaws I4 hereinbefore described, and with which are cooperable removable jaws I5a that are identical with the first mentioned jaws I5. As shown, and as will be understood, the jaws I4 are provided with pins corresponding to the pins and the jaws I5a at their rear edges are provided with notches corresponding withy the aforementioned notches 2I to engage the pins 20.

IThe Vbody II in the underside thereof is also suitably recessed to accommodate the adjustment plate 23 which is hinged to the body II as at22.

An adjustment screw 25 is threadedly engaged with theV forward portion of the body II in a manner to engage the plate 23' for varying the angular relative position of the body II' and the plate 23 in obtaining the desired Contact of the blade with the grindingy disk. 'I'he plate 23', when not to be used, will be also held in fixed position through the medium of a suitable screw This second form of blade holder and clamp is used in substantially identically the same manner as the rst form of blade holder and clamp is used and as hereinbefore clearlyvdescribed relative to the rst form of blade holder and clamp.

What is claimed is:

1. A blade `holder of the character described comprising a "substantially flat body, strips secured to one side of the body and extending transversely thereof, .said strips being provided at one end with jaws projecting beyond an edgeY named jaws, and means for securing the removable jaws to the strips in operative'positions relative to the rst named jaws, said removable jaw lbeing provided with a slot therein, aV pin on the first named jaw receivable in said slot, said body in said one side thereof and between the'strips being provided with a recess, an adjustment plate normally arranged in the recess and hinged to the body, and an adjustment screw threaded to the body to engage the adjustment plate.

GREGORY MAKAROFF. 

